Amazon has fired another salvo in the virtual assistant wars by opening up access to the far-field voice recognition technology found in its Echo smart speakers so that third-party manufacturers can make their own versions (via BBC).

The move comes as Amazon attempts to spread the use of its Alexa virtual assistant across a wide range of connected products and take ownership of a larger portion of the growing smart devices market. Google announced its branded Home smart speaker in November, while Apple is also rumored to be planning a similar Siri-enabled device this year.

The initially invite-only access to the technology via the Alexa Voice Service program will give manufacturers the right to replicate the Echo’s seven-microphone array that allows the speakers to hear a voice command from across the room.

The access also means third-party developers can use the proprietary algorithms used for wake-word recognition, which focus the array on the owner’s voice and filter out echoes and other noises. Developers will be provided with a reference kit as a starting point for their own designs, and the freedom to source components from a range of parts manufacturers.

“Our vision is for Alexa to be everywhere, and that means making it available to other companies and services to integrate into a wide range of devices,” said an Amazon spokesperson.

“We expect Alexa to be in many devices over time, including products that compete with Echo, which is why we’re investing in making a wide range of hands-free and far-field reference solutions available to OEMs [original equipment manufacturers].”

Amazon’s rollout of Alexa has gained steam ever since CES 2017 in January, when the virtual assistant cropped up in a range of products including third-party smart speakers, cars, TVs, lamps, and even refrigerators.

In February Amazon announced it was extending third-party support for its Alexa Voice Service (AVS) internationally, and last month it added its Siri competitor to the company’s iOS app, allowing users to search Amazon, track orders, play music, and start audio books from Audible.